Apparatus and method of making molds



Oct. 18, 1960 H. P. PEASLEY 2,956,317

APPARATUS AND METHOD OF MAKING MOLDS Filed July 22, 1957 a Sheets-Sheet1 INVENTOR. HO ARD PEASLEY BY i Am A mih/virs 1960 H. P. PEASLEY2,955,317

APPARATUS AND METHOD OF mxmq MOLDS Filed July 22, 1957 3 Sheets-Sheet 2V I 6 22 w IN VEN TOR.

BY H ARD PEASLEY v AITO Oct. 18, 1960 H. P. PEASLEY 2,956,317

APPARATUS AND METHOD OF MAKING MOLDS Filed July 22, 1957 3 Sheets-Sheet3 FIG. 3

/ INVENTOR.

ARD PEASLEY BY FIG. 4 I! Q 1 M APPARATUS AND METHOD OF MAKING MOLDSHoward P. Peasley, Horsheads, N.Y. (15 Brooklyn St., Portville, N.Y.)

Filed July 22, 1957,'Ser. No.673,517

8 Claims. (Cl. 22-21) This invention relates generally to apparatus andmethods for making molds, and more particularly to methods for packingsand in a mold box around apattern or patterns located the mold bo'x.

Heretofore, in prior known molding machines wherein a fiem'ble diaphragmor obtruder'has been employed for packing sand in a mold box, theflexible diaphragm 'has been secured'to ahead and after the pattern habeen placed in the mold box and the mold box has been filled with sandor molding agent, the mold box has been brought under the head. The headcarries the fiexible diaphragm, which, in the operation of the machine,can be drawn upwardly into the head to make room for sliding themold'box under the head, and

which is then expanded to compress the sandin the mold box tightlyaroundthe pattern, thus compacting the sand.

This method of compressing sand in a mold 'box by the application ofpressure to the sand through the diaphragm results in a mold which isvery hard and uniform at the surface where the diaphragm contacts thesand but which diminishes in uniformity and hardness through the mold'to the pattern. Air consumption is considerable, due to the spacenecessary in the head to accommodate withdrawal of the diaphragm.Outward thrust on the sides of the mold box is considerable, makingnecessary the use of heavily reinforced mold boxes. Velocity ofcompression is limited by the size of air lines to the headand the spacenecessary in the head to accomplish the Withdrawal of the diaphragm.Uniformity varies with the complexity of the ,patternbeing molded andthe m-ixture of the sand being used.

Finally, in all the methods now in use in molding machines, it is thecommon practice to exert pressure on the sand to compress the sand inthe mold box and thus bring it into contact with the pattern to form themold. As a result, the pressure at various points on the pattern isnotuniform and particularly at corners or crevices or other indented areasthe resulting mold leaves much to be desired.

Accordingly, it is a prime object of this invention in overcoming theabove objections to provide the ram or platen to which the pattern maybe attached and to which variable pressures and velocities can beexerted to suit various molding requirements, such as complexity andnumber of patterns and variations in sand mixtures.

Another important object of my invention is to provide a machine inwhich the pattern or patterns are held in place on "a platen and rammedor driven into the sand under pressures and at velocities which can bevaried to suit individual requirements.

A further object of my invention is to provide a molding machine forcontinuous operation incorporating all the operations of making acomplete mold, ready fo'r pouring.

Still another object is to exert pressure to the sand at United StatesPatent i Patented Oct. 18, 19.60

the pattern surface, and, by a novel means which will complished, by'amethod whereby the pattern is driven or rammed into the sand or otherfinely divided material, instead of attempting to pack or compress thesand around a stationary pattern. The invention also includes apparatusfor carrying out the above method, which apparatus comprises a platen ormeans for holding a pattern in conjunction with a ram, or other meansfor driving a patterninto sand or other'finely divided material to forma mold.

The'invention will be better understood when the following descriptionis taken in reference to the accompanying drawings in which:

Fig. l is a cross sectional elevation ofmy machine, in part, showing theprinciple of my invention, with the machine ready for molding.

Fig. 2 is a cross sectional elevation as in Fig. l, but with the machineexecuting a mold.

Fig. 3 is'a side elevation of an embodiment of the molding machine inaccordance 'with my invention.

Fig. 4 is a reduced top plan view on the line 4-4, Fig. 3, showing thelayout in a rotary table.

Fig. 5 is a cross sectional view, in part, -of a part of my machineillustrating various features'thereof.

Fig. 6 is a cross sectional view on the line 6-6, Fig. 3, of acompleted, ready to pour, mold asproduced by my machine.

With reference now to Fig. 1, the principle of my invention isillustrated by a hydrostatic container 27 having fastened about itsupper periphery adiaphragm 3t) and partially filled with anon-compressible liquid 28. A'perforated support plate 29"is containedincontainer 27 so that the diaphragm 3th may be centrally supported. Aconnecting line Slconnects container 27 through a two-way valve 32 toa-displacement cylinder 34. Displacement cylinder 34 has within it apiston'33 connected by a suitable rod 35 to a "piston '38 in anoperating cylinder 36. Rod 35 has at its uppermost end a locknut 37which is adapted to limit the length of downward travel of rod 35. Twolines 49 and 41 serve alternately as pressure and exhaust lines for thepurpose of moving piston 38 upwardly'or downwardly in cylinder 36.

An impact platen 21 is suspended-from an impact cylinder (not shown) bya shaft 22 and has on its lower surface the desired pattern "20.Suitable sand shields 23 of 'yieldable spring steel or the like arefastened about the lower perimeter of the platen 21.

Above the diaphragm 30 of the hydrostatic container 27 is a suitableflask 26 and an upset 25.

In the operation, as in Fig. 1,;pressure, for instance,

air, is applied to line 41 into cylinder 36, thus moving piston 38upwardly and exhausting air from the upper po'rtion of cylinder 36. Rod35 accordingly moves piston 33 upwardly and, valve 32 being open, allowsnoncompressible liquid 28 tobe displaced into cylinder 34. 'Thusdiaphragm 30 is brought to rest on perforated plate 29. Flask '26 andupset 25 are then filled with the desired amount of molding sand 24.Pressure'is then applied into line 40, moving the piston 38 downwardlyand exhausting air through line 41 and correspondingly moving piston 33downwardly in cylinder 34, thus displacing liquid 28 back through line31 through valve 32 into hydrostatic container 27. Valve 32 is thenclosed. The amount of liquid 28 displaced into container 27 iscontrolled by the distance of travel of the rod 35 with pistons '33 and38 thereon. Locknuts 37 are adjusted according to the displacement ofliquid 28 desired to mold to a given pattern 20.

With reference now to Fig. 2, liquid 28 having been displaced back intocontainer 27, diaphragm 30 is thus suspended above plate 29. Impactplaten is released and shaft 22 drives platen 21 downwardly, drivingpattern into the molding sand 24. Velocity of the platen 21 iscontrolled by a power operated impact cylinder (not shown) and thepressure is controlled by the amount of weights (not shown) on the shaft22. Sand shields 23 scavenge the molding sand 24 within flask 26 and thesurface of the platen 21 becomes the parting line of the mold. As thepattern 20 is driven into the sand 24, the most pressure is at thesurface of the pattern 20. Since the pattern 20 extends downwardlybeyond the plane of the platen 21, the tendency will be to displace partof the molding sand 24 directly under the pattern 20. Thenon-compressible liquid 28 being confined within hydrostatic container27 is thus displaced from underneath the pattern 20 towards the sides ofthe container 27. Flexible diaphragm 30 is displaced upwardly around thesides of the pattern 20, thus further compacting the sand 24 in themold.

It will be readily apparent to those skilled in the art that this methodis highly advantageous over previous methods in that the molding sand iscompacted uniformly around the pattern surface instead around thediaphragm surface, thus providing for a casting of higher quality. Largevolumes and pressure of compressed air required in previous methods arenot needed in my method as only a small volume of low pressure air isrequired to actuate operating cylinder 36 in order to displace theliquid 28. Thus efliciency is achieved.

Construction of a hydrostatic impact molding machine with six-stationrotary table is illustrated in Figs. 3, 4 and 5. A six-station rotarytable 65 is rotatably mounted around a central post 58 on a base 67.Supporting members 57 on post 58 are adapted to hold the impactcylinders 50, 51, and push-out cylinder 59. A suitable sand hopper 66 isalso held in position over the table 65. Cope impact cylinder 51 anddrag impact cylinder 50 are mounted over adjacent stations of the table65. For purposes of reference, the drag impact cylinder 50 will bedescribed. Platen 21 is mounted at the lower end of shaft 22 which isactuated by the power cylinder 50. This cylinder 50 is a double-actingpower cylinder and is adapted to drive shaft 22 downwardly and retractshaft 22 upwardly by means of fluid pressure. This is not elaborated onas it is a standard cylinder. A squaring bar 56 is fastened to platen 21and runs through suitable guides forinsuring that platen 21 is at alltimes in exact alignment with the underlying flask. At the top end ofshaft 22 is a suitable weight 52, the amount of which may be varied asrequired by the particular pattern being used. Triggering toggle levers54 are adapted to be actuated and unlocked by an actuating plunger 55.Sand hopper 66 is kept filled with molding sand and is adapted to filleach flask in succession at a filling station. A push-out platen 61 isoperated by a suitable push-out power cylinder 59 and shaft 22x, and hasa squaring bar 56x. A receiving platen 62 is vertically movably mountedin any desired manner on base 67 so as to be elevated under rotary table65 to receive without dropping the finished molds 64; and a strokingplunger 68 is adapted to push the finished mold 64 from platen 62 onto aconveyor 63. The cope impact cylinder 51 is constructed the same as thedrag impact cylinder 50.

In Fig. 4, taken along line 4--4, Fig. 3, a reduced plan view of thelayout of rotary table 65 is illustrated showing the six stations.Rotation is counterclockwise, as indicated by the arrow (Fig. 4).Referring to Fig. 4 in view of Fig. 3, station 3 would be under the sandhopper 66, station 2 under the cope impact cylinder 51, station 1 underthe drag impact cylinder 50, stations 6 and 5 ready for operations to bedescribed further, and station 4 under the push-out cylinder 59.

In the operation of the machine, let us assume that the machine isoperating continuously and the stations are positioned momentarily asshown in Fig. 4. As the machine rotates 60, it moves one station. Ateach alternate table, a complete mold 64 is pushed out onto thereceiving platen 62.

With reference to Fig. 4, the simultaneously steps at the stations 1-6(Fig. 4) rotating countercolckwise are:

Station 3, fill cope flask with sand;

Station 4, push-out completed drag mold;

Station 5, roll over completed cope (to be further described);

Station 6, place core in ready drag mold (to be described);

Station 1, cope flask with waiting to be molded;

Station 2, drag flask with sand therein waiting to be molded.

After the table 65 moves one station, the following is done:

Station 1, form drag mold;

Station 2, form cope mold;

Station 3, fill waiting drag flask with sand;

Station 4, push-out completed cope onto previously pushed out dragwaiting on receiving platen 62;

Station 5, next drag mold with core waiting to table and to be pushedout onto platen 62;

Station 6, cut sprue hole in finished cope mold.

From the above it is obvious that on .each alternate rotary tablestation the machine sends a complete, ready to pour mold onto a conveyorto go to the casting room. The operator need only start the machine andcut the sprue hole and insert a core where used. The sprue 79 is thesmall opening through which molten metal or the like is poured into themold. A core is a pattern device (not shown) which is placed so as toleave a hollowed center of desired dimension in the casting. The cope isthe top half of the mold 76, and the drag is the bottom half 77,separated at the parting line 78 of the finished mold.

Fig. 5 is a modification of a portion of the machine shown in Fig. 3,enlarged and in part, cross-sectioned. It is herein illustrated that thebase 67 is used to contain the operating cylinders 34 and 36 andassociated valve 32 and line 31 for the hydrostatic container 27 shownin Figs. 1 and 2. A complete assembly of each is located under the copecylinder 51 and the drag cylinder 50. Base 67 also contains thepower-operated stroking plunger 68 (not shown). This plunger 68 may be aconventional pneumatic or the like cylinder with a predetermined lengthof stroke. In Fig. 5, flask 26 is illustrated as mounted on trunnions81. A power-operated cylinder 80 is adapted to turn flask 26 ontrunnions 81 through any desired arrangement. A modified embodiment ofcylinders 34 and 36 is illustrated herein. As hereinbefore described,the cope mold is automatically rolled over at station 5 on the trunnions81 after sprue hole has been cut at station 6.

With reference to Fig. 6, a completed mold 64 is illustrated incross-section. 'Ihis mold 64 is the same as is pushing out ontoreceiving platen 62. A drag 77 and a cope 76 are separated at theparting line 78. A core, if desired, is disposed within the mold and isdesignated by the reference 75x. A sprue hole 79 is shown as cut intothe cope 76.

Thus it is seen that the present invention presents several advantagesover the methods and apparatus in the prior art. The machine isautomatic. At each alternate rotary table, a complete mold is ready forpouring. The new principle of molding provides a means for adjusting thelocation of the parting line and insures maximum efiiciency during themolding operations. By ramming the pattern into the stationary sand orother comminuted material under pressure and at a relatively highvelocity the molding sand is compacted uniformly and tightly at thepattern surface instead of at the diaphragm surface, as in the priorart. Low volumes and low pressures of fluid under pressure are requiredfor operation of the machine, as contrasted with the prior art methodsand machines.

It is to be understood that further modifications may be made which donot depart from the spirit of the appended claims.

I claim:

1. In a molding machine, a hydrostatic container closed at the bottomand open at its top; a flexible diaphragm closing the open top of saidcontainer; said container having a non-compressible liquid therein belowthe diaphragm; a cylinder having a piston; a valved duct extending fromsaid container to said cylinder; means for moving the piston in saidcylinder; a flask disposed upon said container and filled with moldingsand; an impact platen above said flash carrying said pattern andadapted to be forcibly depressed into said sand; said machine having amultiple station rotary table adapted to rotate around a central postmounted on a base containing power cylinders for operating said table;said machine having means for simultaneously molding a cope mold and adrag mold; and said machine having means for rolling over said cope moldonto said drag mold including trunnions fastened to the flask.

2. In an impact molding machine in accordance with claim 1, saidtrunnions being power operated for rolling over said flask.

3. In a molding machine, a hydrostatic container closed at the bottomand open at its top; a flexible diaphragm closing the open top of saidcontainer; a central perforated plate in the bottom of said containerdisposed below said diaphragm; said container having a non-compressibleliquid therein below the diaphragm; a cylinder having a piston; a valvedduct extending from said container to said cylinder; means for movingthe piston in said operating cylinder; a flask disposed upon saidcontainer and filled with molding sand; an impact platen above saidflask carrying said pattern and adapted to be forcibly depressed intosaid sand; said machine having a multiple station rotary table adaptedto rotate around a central post mounted on a base, containing powercylinders for operating said table, said machine having means forsimultaneously molding a cope mold and a drag mold; and said machinehaving means for rolling over said cope mold onto said drag moldincluding trunnions fastened to the flask.

4. In an impact molding machine in accordance with claim 3, saidtrunnions being power operated for rolling over said flask.

5. In a molding machine, a hydrostatic container closed at the bottomand open at its top; a flexible diaphragm closing the open top of saidcontainer; a central perforated plate in the bottom of said containerdisposed below said diaphragm; said container having a non-compressibleliquid therein below the diaphragm; a cylinder having a piston; a valvedduct extending from said container to said cylinder; an operatingcylinder; a second piston in said operating cylinder, a rod connectingsaid first and second pistons; means on said rod for varying the strokeof said pistons; means for moving the second piston in said operatingcylinder; a flask disposed upon said container and filled with moldingsand; an impact platen above said flask carrying said pattern andadapted to be forcibly depressed into said sand; said machine having amultiple station rotary table adapted to rotate around a central postmounted on a base containing power cylinders for operating said table,said machine having means for simultaneously molding a cope mold and adrag mold, said machine having a power cylinder and push-out platen forpushing completed molds onto a receiving platen and thence to aconveyor, said machine having a power operated stroking cylinder forpushing said mold onto said conveyor, said machine having means forrolling over said cope mold onto said drag mold including trunnionsfastened to the flask, and said trunnions being operated by power andadapted to roll said flask over on its axis.

6. In a molding machine, a hydrostatic container closed at the bottomand open at its top; a flexible diaphragm closing the open top of saidcontainer; a central perforated plate in the bottom of said containerdisposed below said diaphragm; said container having a non-compressibleliquid therein below the diaphragm; a cylinder having a piston; a valvedduct extending from said container to said cylinder; an operatingcylinder; a second piston in said operating cylinder, a rod connectingsaid first and second pistons; means on said rod for varying the strokeof said pistons; means for moving the second piston in said operatingcylinder; a flask disposed upon said container and filled with moldingsand; an impact platen above said flask carrying said pattern andadapted to be forcibly depressed into said sand; trunnions mounted onsaid flask for rolling over of said flask, said trunnions being poweroperated for rolling over said flask.

7. In a molding machine, a hydrostatic container closed at the bottomand open at its top; a flexible diaphragm closing the open top of saidcontainer; a central perforated plate in the bottom of said containerdisposed below said diaphragm; said container having a non-compressibleliquid therein below the diaphragm; a cylinder having a piston; a valvedduct extending from said container to said cylinder; an operatingcylinder; a second piston in said operating cylinder, a rod connectingsaid first and second pistons; means on said rod for varying the strokeof said pistons; means for moving the second piston in said operatingcylinder; a flask and superimposed upset disposed upon said containerand filled with molding sand; an impact platen above said upset carryingsaid pattern and adapted to be forcibly depressed into said sand; andsand shields of yieldable spring material mounted around the peripheryof said platen, said diaphragm being adapted to be displaced towardssaid pattern by displacement of said non-compressible liquid forcompacting the sand around said piston; said machine having a multiplestation rotary table adapted to rotate around a central post mounted ona base containing power cylinders for operating said table, said machinehaving means for simultaneously molding a cope mold and a drag mold;said machine having a power cylinder and push-out platen for pushingcompleted molds onto a receiving platen and thence to a conveyor, saidmachine having a power operated stroking cylinder for pushing said moldonto said conveyor, said machine having means for rolling over said copemold onto said drag mold including trunnions fastened to the flask; andsaid trunnions being operated by power and adapted to roll said flaskover on its axis.

8. In a molding machine, a hydrostatic container closed at the bottomand open at its top; a flexible diaphragm closing the open top of saidcontainer; a central perforated plate in the bottom of said containerdisposed below said diaphragm; said container having a non-compressibleliquid therein below the diaphragm; a cylinder having a piston; a valvedduct extending from said container to said cylinder; an operatingcylinder; a second piston in said operating cylinder, a rod connectingsaid first and second pistons; means on said rod for varying the strokeof said pistons; means for moving the second piston in said operatingcylinder; a flask and superimposed upset disposed upon said containerand filled with molding sand; an impact platen above said upset carryingsaid pattern 7 and adapted to be forcibly depressed into said sand; andsand shields of yieldable spring material mounted around the peripheryof said platen, said diaphragm being adapted to be displaced towardssaid platen by displacement of said non-compressible liquid forcompacting the sand 5 around said piston; trunnions mounted on saidflask for rolling over of said flask, said trunnions being poweroperated for rolling over of said flask. I

References Cited in the file of this patent UNITED STATES PATENTS 65,922Lowell June 18, 1867 8 McCarte Apr. 6, 1915 Bunting et a1. Feb. 23, 1932Beech Dec. 24, 1957 FOREIGN PATENTS Great Britain Mar. 2, 1955 CanadaNov. 15, 1955

